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1.
Abstract

Crown-containing N-(thio)phosphoryl(thio)ureas are related to a class of NH-acids due to the presence of two acceptor-groups: (thio)phosphorylic and (thio)acylic. In agreement with structure of lariat ether, it was observed a stage corresponding to the step ejection of two H* ion on the potentiometric titration curve of ligand by alkaline. Calculated step ionization constants demonstrate that these compounds are weak acids with relative values of pK1 and pK2.  相似文献   

2.
By means of the 1H, 13C, and 31P NMR spectroscopy structure and intramolecular transformations of N,N′-bis[diisopropoxythiophosphorylaminothiocarbonyl]-1,7-diaminoheptane in 3–10% DMSO solutions were studied. High lability of molecule with the realization of two conformers (linear and pincer-like) of macromolecule, of the proton imide-imide exchange, and of different tautomeric forms was proved.  相似文献   

3.
Semiempirical quantum-chemical calculations of the spatial arrangement and electronic structure of the tautomeric forms of N-[diisopropoxy(thio)phosphoryl](thio)benzamides were carried out by the PM3 method. The most energetically favorable forms were revealed, and the reasons for their stabilization were discussed.  相似文献   

4.
The structure and intramolecular transformations of N-phenyl-N′-(diisopropoxythiophosphoryl)thiourea in (CD3)2CO solution were studied by 1H, 13C, and 31P NMR spectroscopy. Combined analysis of NMR data and model calculations gave evidence in favor of high conformational and tautomeric flexibility of the thioureas in solution. The Z,E conformation of the amide form with the two N-H bonds cis and trans to the C=S bond was found to be preferred.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 6, 2005, pp. 908–911.Original Russian Text Copyright © 2005 by Karataeva, Yul’metov, Zabirov, Aganov, Klochkov.  相似文献   

5.
Conclusions The ethyl esters and Na salts of N-(tetramethyldiamldo(thio)phosphoryl)- and N-(dimorpholido(thio)phosphoryl)-cis- and trans-4-ACHC-DL-phenylalanine have been synthesized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 386–390, February, 1980.  相似文献   

6.
Abstract

The analysis of all known synthesis methods of N-(thio)phosphorylthiómides of the common formula RC(S)NHP(X)R'2 (1), where R=Alk, Ar; R'=óIk, ór, SAIk, SAr. Alk, Ar; X=O,S has been gave in this report. We worked out the simple and convenient syntheses methods of this class compounds.  相似文献   

7.
《Mendeleev Communications》2021,31(5):673-676
New pathways of reaction between 1-methylthiourea or 1-methylurea and benzil bring about new derivatives of (2S*,3aR*,6aS*)-perhydro-3aH-[1,3]dioxolo[4,5-d]imidazole and racemic (4S*,5R*)-4-alkoxy-5-hydroxy-1-methyl-4,5-diphenylimidazolidine-2-thiones. Some of the obtained urea-and thiourea derivatives were characterized by X-ray diffraction, which showed their supramolecular organization governed by the directionality of hydrogen bonds at the acceptor side C=O or C=S groups.  相似文献   

8.
Applying the ligand electrochemical parameter approach to sandwich complexes and standardizing to the Fe(III)/Fe(II) couple, we obtained E(L)(L) values for over 200 pi-ligands. Linear correlations exist between formal potential (E degrees ) and the summation operatorE(L)(L) for each metal couple. In this fashion, we report correlation data for many first row transition metal couples. The correlations between the E(L)(L) of the substituted pi-ligand and the Hammett substituent constants (sigma(p)) are also explored.  相似文献   

9.
Herein, we first report an electrochemical methodology for the site-selective alkylation of azobenzenes with (thio)xanthenes in the absence of any transition metal catalyst or external oxidant. A variety of groups are compatible with this electrochemical alkylation, which furnishes the products in moderate to good yields.  相似文献   

10.
A series of novel estradiol-based salicylaldehyde (thio)semicarbazones ((T)SCs) bearing (O,N,S) and (O,N,O) donor sets and their Cu(II) complexes were developed and characterized in detail by 1H and ¹³C nuclear magnetic resonance spectroscopy, UV–visible and electron paramagnetic resonance spectroscopy, electrospray ionization mass spectrometry and elemental analysis. The structure of the Cu(II)-estradiol-semicarbazone complex was revealed by X-ray crystallography. Proton dissociation constants of the ligands and stability constants of the metal complexes were determined in 30% (v/v) DMSO/H2O. Estradiol-(T)SCs form mono-ligand complexes with Cu(II) ions and exhibit high stability with the exception of estradiol-SC. The Cu(II) complexes of estradiol-TSC and its N,N-dimethyl derivative displayed the highest cytotoxicity among the tested compounds in MCF-7, MCF-7 KCR, DU-145, and A549 cancer cells. The complexes do not damage DNA according to both in vitro cell-free and cellular assays. All the Cu(II)-TSC complexes revealed significant activity against the Gram-positive Staphylococcus aureus bacteria strain. Estradiol-TSCs showed efficient antioxidant activity, which was decreased by complexation with Cu(II) ions. The exchange of estrone moiety to estradiol did not result in significant changes to physico-chemical and biological properties.  相似文献   

11.
段文贵  罗常泉  岑波  耿哲 《化学通报》2007,70(9):695-698
在无溶剂绿色化学条件下,将α-萜品烯-马来酸酐加成物(1)与取代苯(硫)脲发生N-酰化反应,合成了4个N-(1-异丙基-2-羧基-4-甲基二环[2.2.2]-5-辛烯-3-羰基)-N'-芳基(硫)脲化合物(3a~3d),并由IR、UV-Vis、MS、1H NMR、13C NMR和元素分析确认了目标产物的结构.生物活性测试表明,其中3个化合物(3a、3b和3c)具有植物激素作用.  相似文献   

12.
It was shown that the reaction of the readily accessible 4-azido-, 4-acetoxy-, 4-arylsulfonyl, 4-ethoxythiocarbonylthio-,or 4-isothiocyanatohexahydropyrimidine-2-thiones/ones and 4-azidotetrahydro-1,3-thiazine-2-thiones with sodium cyanide leads to the selective formation of the corresponding 4-cyano derivatives. The diastereoselectivity of the reactions depends on the structure of the heterocycle and the solvent, and is practically independent of the nature of the leaving group. The preferableness of the axial orientation of the cyano group in the molecules of the compounds synthesized was established; this is explained by the development of the anomeric effect.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1389–1397, October, 1993.  相似文献   

13.
Bo Zhang  Silong Xu 《Tetrahedron》2008,64(40):9471-9479
In this report, the dipolarophile imines with easily removable activating group O,O-diethyl(thio)phosphoryl have been investigated in the nucleophilic phosphine-catalyzed [3+2] cycloaddition reaction of electron-deficient allenes. Under the catalysis of a tertiary phosphine, N-(thio)phosphorylimines readily undergo the [3+2] cycloaddition reaction with ethyl 2,3-butadienoate or ethyl 2,3-pentadienoate, affording the corresponding N-(thio)phosphoryl 3-pyrrolines in moderate to high yields with good diastereoselectivity. Removal of the (thio)phosphoryl group from the adducts has been successfully achieved via the acidic methanolysis of the P-N bond, giving the free amine 3-pyrrolines in fair to good yields without severe aromatization. Thus, a facile synthesis of N-unsubstituted 3-pyrrolines is established from the phosphine-catalyzed [3+2] cycloaddition reaction of allenes with imines.  相似文献   

14.
A new method of electrochemical arylation of complexes of transition metals (Fe, Co, Ni) with N-containing chelate and macrocyclic (dimethylglyoximate, porphyrin, etc.) ligands employs diphenyliodonium salts as arylating agents and permits the synthesis of compounds containing functional groups that are easily reduceable or sensitive to the action of organometallic compounds. A homogeneous redox catalysis (mediator 1,5-dinitroanthraquinone-9,10) reduces the reaction potential to –0.45 V (Ag/AgCl/KCl), thus substantially decreasing the contribution of side processes.  相似文献   

15.
二芳氧基磷酰肼(2a,2b)或二乙氧基硫代磷酰肼(4)与糖基异硫氰酸酯(5a-5b) 反应,生成相应的N-糖基硫代亚脲基—磷酰胺二芳基酯(6a-6d,7a-7d)和N-糖基硫 代亚脲基—硫代磷酰胺二乙基酯(8a-8d).  相似文献   

16.
N-取代吡唑亚甲胺基-N'-取代苯基(硫)脲的合成   总被引:2,自引:0,他引:2  
硫脲;生物活性;N-取代吡唑亚甲胺基-N'-取代苯基(硫)脲的合成  相似文献   

17.
Regioselective reactions of N-(carboxyalkyl)ureas (ureido acids) and N-(aminoethyl)ureas with 1,2-dioxo-1,2-diphenylethane (benzyl) and glyoxal are studied in detail. The structure of the reactants affects the reaction regioselectivity. Acid-catalyzed reactions of glyoxal with 1-[2-(dimethylamino(acetylamino))ethyl]ureas and benzene with ureido acids result mainly in 2,6-di-substituted glycolurils. The structure of 2,6-di(methoxycarbonylethyl)glycoluril is unambiguously established by X-ray diffraction.  相似文献   

18.
19.
Potassium salts of N-(thio)phosphorylthioamides can substitute one, two, or three halogen atoms in chlorinated 1,3,5-triazine molecules to give the products of imidothiyl structure. At low temperature, products of incomplete substitution of halogen in the starting 1,3,5-triazines can be obtained.  相似文献   

20.
徐志栋  冯殿忠 《合成化学》1998,6(3):332-334
首次合成了喹喔啉-2,3-二甲酰胺(Qxda)与3d过渡金属的三种固体配合物:M(Qxda)2cl2(M=Co(I),Ni(I),Cu(Ⅱ)。通过元素分析,摩尔电导,红外光谱,电子光谱,磁化率,热分析等手段对配合物的组成和性质进行了研究。  相似文献   

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